Amir Yacobyhttps://alumni.berkeley.edu/taxonomy/term/10595/all
enPhysics Monopole-y: A Key to a Unified Theory of Everything?https://alumni.berkeley.edu/california-magazine/fall-2017-bugged/physics-monopole-y-key-unified-theory-everything
<div class="field field-name-field-author field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Aubrielle Hvolboll</div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Eighty-six years ago, physicist Paul Dirac theorized the existence of magnetic monopoles; that is, magnet poles that exist independent of each other. Not north and south together. North. And south.&nbsp;Separately.</p>
<p>Nearly a century later, Felix Flicker, a Berkeley theoretical physicist and post-doctoral researcher in the lab of Norman Yao, is working to help prove Dirac’s theory. “There was this sort of philosophical point I was thinking of,” Flicker says. “You can’t have the left end of a stick without the right end, can&nbsp;you?”</p>
<p>Even when broken down to nanometer-sized particles, one fact remains about magnets: North and south poles are invariably found together. “A magnet is called a magnetic dipole,” Flicker explains. “As in, it’s got two poles, a north and a south,” which cannot be separated. As in a bar magnet. But, he goes on to explain, there is an <i>electric</i> dipole, which has “an electron and a positron” at opposite poles. As in a&nbsp;battery.</p>
<p class="pullquote left">Finding magnetic monopoles would help physicists achieve a unified theory of the universe. “All the laws of nature would look a lot nicer if they did exist…. It’s just that we’ve never found the&nbsp;things.”</p>
<p>Why is this phenomenon considered an oddity of physics? “With the electric dipoles, you’re allowed to just pull them apart and you’ve got the two separate charges. For some reason in the <i>magnetic</i> case, you can’t pull them apart,” he says. “Why does it exist as a dipole and not as two&nbsp;monopoles?”</p>
<p>Electricity and magnetism are so closely related that electromagnetism—their interaction—is one of the four fundamental forces of our universe. The only dissimilarity between electricity and magnetism seems to be the existence of electric monopoles—commonly known as charged particles—and the absence of magnetic monopoles. Finding magnetic monopoles would reconcile the two and help physicists achieve a unified theory of the&nbsp;universe.</p>
<p>“All the laws of nature would look a lot nicer if they did exist…. It’s just that we’ve never found the things,” Flicker&nbsp;says.</p>
<p>Lab experiments have produced monopole-like structures, but so far, no one has seen anything more than a simulation. Now, though, with a new detector, ultracold temperatures, and a bit of luck, Flicker and his colleagues may finally be able to observe this phenomenon in a magnetic crystalline material called “spin&nbsp;ice.”</p>
<p>The spin ice in question, an intricate molecular lattice, is grown in Oxford and was sent to Harvard’s NV-magnetometer, one of the few devices equipped to handle the proposed experiment. Run by Harvard’s condensed matter physicist Amir Yacoby, the device has been created to withstand temperatures as cold as 1.5 kelvin, which is about –271.65 degrees Celsius—really, really&nbsp;cold.</p>
<p>The NV-magnetometer relies on individual defects in diamond to scan magnetic fields; it will scan an area of spin ice 10 x 10 nanometers (1 nanometer = one-billionth of a meter) and, if all goes as planned, will record a magnetic monopole pass through in&nbsp;milliseconds.</p>
<p>Flicker says that, if successful, the findings will be the “smoking gun signature” for the magnetic monopole phenomenon. Though not an observation of a new fundamental particle predicted by Dirac, this may get as close to spotting one as scientists ever&nbsp;come.</p>
<p>Magnetic monopole particles are likely extremely rare; Flicker speculates there may be a single particle in every galaxy. In the case of Flicker’s experiment, this will not constitute the observation of a real&nbsp;particle.</p>
<p>“Whenever a particle is detected, it is interacting with the detection apparatus and therefore not fundamental in the strict sense. It’s a <i>quasiparticle</i>, in a loose sense of the word,” he explains. “Of course, we can infer the existence of fundamental particles even if we’ll never see them. Like inferring the existence of an objective universe, even though all our experiences of it are&nbsp;subjective.”</p>
<p>Practical uses of magnetic monopoles are tricky. As can often be the case with physics, not every discovery has a straightforward practical application. Flicker has a few speculations for monopole use: “magnetricity” and computer memory. If magnetic monopoles can wander through spin ice, then they may be able to flow like electrons in an electric current and be harnessed the same way we harness electricity. Magnetricity could potentially be used as a much more compact form of computer&nbsp;memory.</p>
<p>“But these are pretty early stages,” Flicker says. “We’ve got to prove this thing exists. Then hopefully people will get much more interested in trying to implement it in&nbsp;technology.”</p>
</div></div></div><div class="field field-name-taxonomy-vocabulary-15 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even">From the <a href="/california-magazine/fall-2017-bugged">Fall 2017 Bugged</a> issue of <i>California</i>.</div></div></div><div class="field field-name-taxonomy-vocabulary-3 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even">Filed under: <a href="/california-magazine/topic/science-health">Science + Health</a></div></div></div><div class="field field-name-taxonomy-vocabulary-5 field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even">Related topics: <a href="/california-magazine/topic/university-california">University of California</a></div><div class="field-item odd"><a href="/california-magazine/topic/california-magazine">California magazine</a></div><div class="field-item even"><a href="/california-magazine/topic/cal">Cal</a></div><div class="field-item odd"><a href="/california-magazine/topic/uc-berkeley">UC Berkeley</a></div><div class="field-item even"><a href="/california-magazine/topic/berkeley-alumni">Berkeley Alumni</a></div><div class="field-item odd"><a href="/california-magazine/topic/physics">physics</a></div><div class="field-item even"><a href="/california-magazine/topic/paul-dirac">Paul Dirac</a></div><div class="field-item odd"><a href="/california-magazine/topic/felix-flicker">Felix Flicker</a></div><div class="field-item even"><a href="/california-magazine/topic/norman-yao">Norman Yao</a></div><div class="field-item odd"><a href="/california-magazine/topic/berkeley-physics">Berkeley Physics</a></div><div class="field-item even"><a href="/california-magazine/topic/theoretical-physics">theoretical physics</a></div><div class="field-item odd"><a href="/california-magazine/topic/magnetic-dipole">magnetic dipole</a></div><div class="field-item even"><a href="/california-magazine/topic/electric-dipole">electric dipole</a></div><div class="field-item odd"><a href="/california-magazine/topic/magnetic-monopoles">magnetic monopoles</a></div><div class="field-item even"><a href="/california-magazine/topic/unified-theory-universe">unified theory of the universe</a></div><div class="field-item odd"><a href="/california-magazine/topic/spin-ice">spin ice</a></div><div class="field-item even"><a href="/california-magazine/topic/oxford">Oxford</a></div><div class="field-item odd"><a href="/california-magazine/topic/harvard-nv-magnetometer">Harvard NV-magnetometer</a></div><div class="field-item even"><a href="/california-magazine/topic/amir-yacoby">Amir Yacoby</a></div><div class="field-item odd"><a href="/california-magazine/topic/quasiparticle">quasiparticle</a></div><div class="field-item even"><a href="/california-magazine/topic/magnetricity">magnetricity</a></div><div class="field-item odd"><a href="/california-magazine/topic/galaxy">galaxy</a></div></div></div><div class="field field-name-field-photo-credit field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Image source: Aubrielle Hbvolboll</div></div></div>Wed, 13 Sep 2017 21:45:04 +0000Sara.Beladi7718 at https://alumni.berkeley.edu